The present invention relates to a system for high-speed communication using the Transmission Control Protocol (TCP), or a similar protocol, which requires a host to acknowledge the receipt of data.
The TCP protocol, as documented in RFC (Request For Comments) 793, is widely used for high reliability data communication and has functions for error correction, flow control, etc. According to the TCP protocol, when a receiver host receives data, it sends an acknowledgement to a sender host. Where TCP communication is carried out through a link with a large delay, the time interval between the transmission of data by the sender host and its receipt of the acknowledgement may be considerable. This may lead to the TCP window of the sender host becoming full as further data cannot be transmitted until the acknowledgement for the previously transmitted data packets from the receiver host has been received. Thus, in conventional TCP communication through a large-delay link, though the transmission rate of the delay link may be high, the bandwidth may be utilized inefficiently because of this inherent constraint in the TCP protocol.
One solution to this problem would be to modify the TCP protocol to reduce the effect of the link delay. It is technically possible to improve the TCP protocol. However, this would require the simultaneous reconfiguration of several thousands or more communication apparatuses, rendering this solution impractical.